What to Eat to Bag That Peak

Interviewer: If you love hiking and backpacking, what you eat at high altitude might be a little bit more different than what you eat at low altitude. We'll talk about that next on the Scope. Medical news and research from University Utah physicians and specialists you can use for a happier and healthier life. You're listening to the Scope. We're talking with Stacey Wing-Gaia, registered dietitian and director of the sports nutrition program the University of Utah about high altitude nutrition, specifically for people who go on hikes, backpacks, are at high altitude, and I'm curious to find out if it applies to day-to-day life in Salt Lake City. We'll get to that in a second, though. But, this is your passion. You go hiking at high altitude locations. What are some of the problems when it comes to eating, versus what I eat every day?

Stacey Wing-Gaia: In terms of differences, I think the biggest thing is to kind of understand what altitude is. Most people won't really be affected too much nutritionally, when we're talking at maybe 6,000 feet even. Although some people do get sick if they're coming from sea level. So, generally, I'm talking at 8,000 or higher. Your nutrition is largely affected by the illness that you may experience. When people are not feeling good, when they have what we call acute mountain sickness, they, generally, their appetite goes way down. And so they're not getting enough calories. So, when we're looking at nutrition, one of the biggest things is carbohydrates, particular important.

Interviewer: Even more so than protein?

Stacey Wing-Gaia: Yes, for shorter stays. Protein...again, carbohydrates are still going to be your primary fuel source. So you want to make sure, and particularly in terms of exercise, you're going to fill up your glycogen stores. And so you need that for your muscles.

Interviewer: Would my preparation for the glycogen stores begin actually before we go on the hike?

Stacey Wing-Gaia: Yes.

Interviewer: A week or two before?

Stacey Wing-Gaia: Yeah.

Interviewer: How far in advance, and what would your diet look like?

Stacey Wing-Gaia: Well, interestingly enough, you've all heard about carbo- loading, and several people do it before marathons. But really what they've found is, just follow a high carbohydrate diet, at least about three days beforehand. And you're pretty much good to go. I have something I do with hiking and backpacking, particularly at altitude, is to really encourage people to be snacking frequently while they're hiking or climbing, or whatever it may be. And then also when they go to set up camp, unless of course there's an impending thunderstorm or something, where you need to get out of the weather, that you have a small carbohydrate and protein snack right before you set up camp.

Interviewer: When you say high carbohydrate, what percentage of your calories should be coming from carbs?

Stacey Wing-Gaia: Well, you know, as a sports dietitian, we don't like to talk in terms of percentages.

Interviewer: Oh, okay. How do you like to talk?

Stacey Wing-Gaia: We actually talk in terms of body weight.

Interviewer: Oh, okay.

Stacey Wing-Gaia: And the reason is that you can say, if you don't have very many calories for instance, say, you're supposed to be eating about 4,000 calories, and you're only eating, what, 1,500 or half of what you need, and you say, "Oh, you're supposed to eat 60% carbohydrates." That's not actually enough carbohydrate to fill your muscle. So we talk in terms of, usually, kilograms of body weight. And so, usually we're looking at about 6-10 grams per kilogram of body weight.

Interviewer: 6-10 grams per kilogram of body weight of carbohydrates.

Stacey Wing-Gaia: Yeah, exactly.

Interviewer: And what about protein? Since we're talking about nutrition.

Stacey Wing-Gaia: Yeah. And protein, that's been an area that I've been researching because if you're at altitude for very long. Actually I shouldn't even say for very long, there seems to be some acute responses to altitude. And that the switch that seems to turn on protein synthesis seems to get turned off by hypoxy or low oxygen environment. And also the switch to increase breakdown of protein is turned on. So basically you're breaking down more muscle, and you're not building it. Again, if you're going out for a day or two, it's not going to make a really big difference. You'll go back into a positive nitrogen balance when you return. But if you're going to be out there for any length of time, well, if you lose muscle, and we're not just talking about having big biceps or something. We're talking about impairing physical performance, impairing your immune function. If you're on an expedition, that can increase your risk of injury, it can really affect the whole success of the expedition, I guess you would say.

Interviewer: How do you prevent that? It sounds like everything is going against you.

Stacey Wing-Gaia: Well, yeah. It's true. And there is some theory, and this would be true, that if you think about it, in periods of starvation your body is trying to conserve. So it doesn't really want to build muscle when you're in an environment where you don't have enough calories and you're really stressing the body.

Interviewer: So in the instance of a 2 or 3 days backpack trip at altitude, above 10,000 feet, how many calories above and beyond what you normally eat should you get?

Stacey Wing-Gaia: That's a good question. And of course, as a dietitian, when I say that it really depends because you have to look at the size of the person. There are a few studies that look at energy expenditure, and even on just our trek. But I would say your total caloric intake, anywhere from about three to 5,000 calories.

Interviewer: Okay.

Stacey Wing-Gaia: So, not, I mean, not huge, if you compare it to a Tour de France cyclist where you're looking at 10,000 calories or something. So it's less than that.

Interviewer: So three to five when you're doing that. What would a guy my size, 175, what would I be taking in normally? Just so we can get that comparison.

Stacey Wing-Gaia: Yeah, probably around...are you active?

Interviewer: Fairly.

Stacey Wing-Gaia: Probably about 3,000.

Interviewer: That's what I would be eating normally on a day to day basis.

Stacey Wing-Gaia: Yeah, probably. About 2,500 to 3,000.

Interviewer: And I want to crank that up to 5,000.

Stacey Wing-Gaia: So I would say maybe about an extra. Again, you know, if it's a rest day, not a whole lot. But maybe about 500 calories?

Interviewer: Okay.

Stacey Wing-Gaia: Something like that. Obviously, on the really strenuous days, I would, closer, maybe, to even a 1,000.

Interviewer: And it's pretty important that you do that?

Stacey Wing-Gaia: Yes.

Interviewer: Okay. Any final thoughts on high altitude nutrition, and kind of the average guy, for my trek?

Stacey Wing-Gaia: You know, a lot of the same principles for good nutrition still apply, but the nice thing is to not deny yourself those nice little chocolate treats, and the simple sugar. I have met people with backpacking, they're still very against sugar. You know, sugar is actually a good friend to you on the trail. And you need the quick energy. But you need the protein, so again, having those combinations. Something I like to do, setting up camp, is eat my little bag of granola, that you put some powdered milk in, and then you just add some water, and eat that up. And you get the whey protein in there, and you get the carbohydrate, you get a little bit of fat. And then you have your good dinner. And then if you're in cold weather, having a little snack before bedtime can help rev up that metabolism so you stay warmer.

Interviewer: We're your daily dose of science! Conversation, medicine. This is the Scope. University of Utah Health Sciences radio.